In a mobile phone and other battery-powered embedded systems current consumption is typically an important issue. Therefore a low-power state such as a sleep state may be applied as much as possible in order to reduce current consumption in such as device. Wake-up from such a sleep state is an important parameter for power consumption. A wake-up event can originate from various sources, like user interaction, but also scheduled activities. Efficient approaches for the wake-up from a sleep mode are desirable.